Method and apparatus for determining the color of a liquid



June 20, 1939. M. PHILIPSEN METHOD AND APPARATUS. FOR DETERMINING THECOLOR OF A LIQUID Filed March 3, 1937 FIG. 4.

MICHAEL PHILIPSEN INVENTOR ATTORN QZ Patented June 20, 1939 l I I UNITEDSTATES PATENT. OFFICE METHOD AND APPARATUS FOR DETERMIN- ING THE COLOROF A LIQUID Michael Philipsen, "edbaek, near Copenhagen,

Denmark Application March 3, 1937, Serial No. 128,713

In Denmark January 28, 1935 13 Claims. (01. 88-14) This inventionrelates to a method and aptherefore, necessary to usea standard colorwhich paratus for testing the concentration of a liquid both inintensity and color exactly corresponds to by comparing the color ofthat liquid to color the blood. It has been tried unsuccessfully in thestandards of known value, and more particularly past to compare anunreduced and unhemolysed 5 to the measuring of the hemoglobin contentof, specimen in a very thin layer to a standard ruby 5 blood. Theprimary object of the invention is to glass wedge, the thickness of thewedge at the. provide such a method and apparatus whereby point of colorcoincidence indicating the hemothese measurements can be made to a highdeglobin concentration. A ruby wedge of glass is gree of precisenesswithout the necessity of dilutnot dichromatic, that is, the wedge variesonly .10 ing in any noticeable degree the liquid tobetested, inintensity but does not show the nuances of In all of the colorimetricmethods which have color from the thinnest to the thickest portion. beenadopted heretofore, it is necessary to dilute It has been found,however, that blood can be the liquid to be tested materially in orderto obcompared W Such a y glass When using a tain a color which indicatesthe concentration candle, the li of which is p lacking in within thenecessary limits. In fact it is quite violet, blue and gree y thusrendering vthe 15 usual in the testing of the hemoglobin content bloodundichromatic. However, with this method of blood t dil t th bl d moreth 100 t the contrast of the blood of various concentra- These processeswherein it is necessary dilute tiOIlS has been diminished SO much that acareth bl d h many disadvantagessince it is ful determination of thebloods hemoglobin con- 2 impossible even in the laboratory to dilute thet within t required narrow limits a be blood so precisely as to meet thehigh standards materially pp demanded by the physicians t, s usuallyneces- The invention herein described discloses a new sary to conductthe tests on several,solutions and manner of testing undiluted blood p sin a to take an average reading in order to eliminate light Whichproduces n e e nc eases the 26 the influence of inaccurate dilution.Former atcontrast by the dichlomfl-tic efiect- Thus it has tempts totest such liquids without dilution have been found that one can use acapillary a er f il d, containing the blood in connection with a scaleIn accordance with the present invention, to Supplied vwithcflmbinations of intensity and reduce the specimen to pure hemoglobin soas (10101 necessary for Comparing b d of Variou 30 t i i t t influ n offlu tu ti in concentrations. In the preferred form described 30 oxygencontent of the blood, a reducing chemical herein, the capillary Chamberis pe in such as sodium hydrosulfite h b found order that one, or at themost, a very few standard cessful, and this substance is so effectivethat it @0101 glasses Win be necessary and which glasses can be used insuch small amounts that its volume can easily be made to correspond to ablood will not influence the concentration to any notice- Sample of adefinite concentration and layer 35 able degree. In order to render theblood transthickness- The Capillary am u forms a parent so that it maybe compared with the color natural blood-wedge and this combination canstandards, a hemolysing chemical, for example, readily be used in alight containing dichromatic saponin, has been used which, like thesodium rays by filtering this light by means of complell fl has no pp ea e d uti f c mentary coloring and the contrast can be in- 40 on thesample, It has been found particularly creased to amateria1extentefiectlve compound both of Fhese chemlcals One form of the inventionparticularly adapted m for mstance 30% sa'pomn and of to serve as ahemoglobinometer is shown in the sodium hydrosulfite so that thehemolysation and a complete reduction of the, bloods oxyhemogg igz igifgxfi g gfi d globin to red hemoglobin can be produced eff g d h b ecaplMy we ficiently and in the shortest possible time. In *"P c thisconnection, in addition to using these ma- Flgure 2 a plan. Vlew of theCapmary cham' terials for reducing oxyhemoglobin to red hemoi I globin,it is possible to further alter the structure e 3 a of an mstrument 50of the blood such as in fully oxidizing it to oxybodymg the mventwn;

hemoglobin d ,1 t m ke h ti of it v Figure 4 is a sectional elevationtaken on the The reduced and hemolysed blood has an inline 4-4 of Figure3'; tensity and a color depending upon the thickness Fi ur 5 is anelevation p y in Section S ow- 65 of the liquid layer and theconcentration. It is, ing a suction glass for" removing a sample ofblood from the wound and for holding the sample during its reduction andhemolysation, and

Figure 6 is a diagrammatic view showing an adaptation of the capillarychamber to a photoelectric system whereby the concentration may beindicated automatically on a suitable meter.

Figure 7 is a sectional elevation of a modification showing the use ofan artificial light contained within the instrument.

The capillary chamber comprises a transparent glass base plate l0 uponwhich is permanently mounted a transparent ledge or supporting member I2. Removably mounted upon the base plate and disposed adjacent the ledgeI2 is a transparent glass member I4 in which the lower side is cut outas shown in Figure 1 so as to form a wedge-shaped chamber l6 when themember I4 is placed upon the fiat plate 10.

Preferably the lower surfaces of the end portions I8 and of the member44 and the upper surface of the base plate l0 are ground smooth as byrubbing these surfaces together with a suitable abrasive or polishingmaterial therebetween so as to provide even contact between the endportions I8, 20 and the base plate l0, and the ledge I2 is provided witha projection 22 adapted to cooperate with a similarly shaped indentationin the member l4 so as to prevent longitudinal movement of the member l4with respect to the ledge l2. The member I4 is also provided with theopenings 24 and 26 at opposite ends of the chamber l6 which openingsprevent the blood from wetting the portions l8 and 20. As shown inFigures 1 and 2 of the drawing, the transparent member I4 is shorterthan the base plate l0 and longer than the ledge member l2 so that thesupporting ends l8 and 28 of the member I 4 may rest on portions of thebase plate which are distant from the ends of the ledge member and whichportions may readily be kept free from dirt which may collect around theends of the ledge member.

The combination of the base plate l0, ledge l2 and member I 4 is adaptedto be placed upon a sloping support 28 of a housing 29, as is shown moreclearly in Figure 4. The support 28 is opaque except for a cut-outportion or window 30 through which the observations are made. The baseplate I0 is slidable in a longitudinal direction on the support 28 withthe m'embers I2 and [4 directly over the window 30 and a pair of indexlines 32 and 34 etched on the base plate will thus cooperaterespectively with scales 36 and 38 suitably inscribed or attached to thefixed support 28.

Within the housing and below the support 28 is another support 40 uponwhich is mounted a glass color filter plate 42 and another color filterplate 44 is supported vertically between the bottom of the housing 29and the upper edge of the support 28. A mirror 46 is mounted on thebottom of the housing 29 below the filter, plate 42 and in a positionsuch that light rays such as 48 from some outside source will enterthrough an opening 50 in the rear portion of the instrument, and willpass through the filter 44 to be reflected from the mirror 46 and passupwardly to the observer through the filter 42, window 30, base plate l6and the combination of ledge l2 and chambered member l4. In this mannerthe light rays pass through a set of color filters and may thus bebrought into a substantially complementary color to that of the bloodspecimen.

A standard color glass 52 is shown as mounted on the upper surface ofthe filter plate 42 in a position such that part of the rays 48 willpass through this standard glass and the ledge l2 to the observer whileanother part of the rays will reach the observer through the blood in asection of the chamber l6 without having passed through this standardglass. Thus, the observer will see in one part of the window 30 beneaththe ledge l2 the standard color of the member 52, and in the other partof the window he will see I in looking through the member l4 the rayswhich pass directly through the blood in the chamber l6 without havingpassed through the standard glass 52.- Thus, the last mentioned part ofthe window will show a. color which is brighter or darker than that ofthe standard glass, depending upon the longitudinal position of thechamber l6 on the supporting plate 28, that is, the color will bebrighter or darker depending on the height or thickness of that portionof the chamber l6 above the window 30, or, in other words, upon theblood layers thickness and upon the concentration of the hemoglobin. Theobserver need only to slide the base plate I0 and thus the chamber l6into a position where both parts of the window show the same color. Hethen may read directly the hemoglobin concentration by the position ofthe index 32 upon the scale 36, or of the index 34 upon the scale 38.

In order to keep at a minimum the amount of blood necessary for asuitable specimen, the instrument is preferably furnished with twostandard colors having different values, and it is for this reason thatthe two scales 36 and 38 are furnished, as well as the two correspondingindexes 32 and 34 showing the hemoglobin concentration. A shutter member54 permits of a selection of one or the other of the the two standardcolors 52 or 56, this shutter member being in the form of a disc pivotedat 58 to the support 28. Attached to one edge of the disc is atongue-like extension 60, and it will thus be seen that by rotating theshutter disc through a few degrees the tongue 60 will cover and thusrender invisible either one or the other of the standard color plates 62and 56. The edge of the shutter disc is provided with a double endedarrow 62, one end of which will always be hidden beneath the support 28while the other end will point toward either the scale 36 or the scale38, depending on which of the color glasses 52 or 56 is visible.

Instead of using color standards of solid glass, these may comprisetransparent glass receptacles filled with a liquid such as hemolysed andreduced hemoglobin.

when assembling the apparatus thus far described, a sample of blood ofknown hemoglobin content is placed in the wedge-spaced chamber I6between the member l4 and the plate in, and the member I4 is then movedor adjusted longitudinally on the plate l0 until color coincidence isobtained between the color of the blood seen through member I4 and thestandard color seen through the lower portion of window 30. The plate Inis previously adjusted on the support 23 so that the index line 32 orthe line 34 coincides with the proper reading on the scale 36 or thescale 38, respectively, depending on which of the two standard colors 62or 56 is being used. When the proper adjustment of the member l4 withrespect to the plate III has been found, the member I2 is permanentlysecured to the plate III as by means of a suitable cement. Theprojection 22 will then hold the member l4 in the proper position.

Since, in accordance with this invention, the

blood sample is not diluted, the usual measuring pipette is dispensableand this is replaced by the small capillary glass receptacle 64,illustrated in Figure 5. The glass 84 has a narrow portion 66 and at theend of this portion is provided with a small hole 68. The upper end ofthe glass carries a rubber rim Ill and by placing the finger on this rimsome of the air within the glass may be forced outwardly through theopening 68, or additional air may be sucked in. In use the glass 64 isheld horizontally with the point of the glass containing the opening 68placed at the wound. The narrow portion 66 then automatically fills withblood, the blood passing through the opening 68 by capillaryattraction.- As soon as the portion 66 is filled the flow will stop andthe necessary quantity .is thus automatically obtained. The primarypurpose of the glass 64 is, however, to permit mixing of the compound ofsodium hydrosulfite and saponin with the blood without the necessity ofbringing the specimen in any closer contact with the air, through whichevaporation would change the concentration and reoxidation wouldcounteract the reduction.

One end of a pin 12, normally maintained in I suitable supports 14 atthe rear of the instrument, is dipped into a small receptacle 16 alsosupported by the instrument, and a few grains of the compound willadhere to the pin and may thus be stirred into the blood in the glass 64where the action of hemolysation can be readily observed. The preparedspecimen can then be pressed out of the glass along the chambered memberl4 and the chamber 96 will fill automatically due to capillary force.When not in use the glass 64 is preferably supported in the instrumentcase, as is shown in Figure 3.

Instead of using as a source, daylight or some artificial light outsideof the instrument, it may be desirable to install an electricincandescent lamp II, in the instrument housing 29 as illustrated inFigure 7, thus eliminating errors which might occur due to pooroutlining of the optical axis or due to variations in the differentlights spectra.

The adaptation of the capillary wedge-formed space l6 to calorimetrypresents another hitherto unavailable advantage. Although there alreadyexist wedge-formed containers forcomparing diluted solutions to standardcolors, these containers are difficult to manufacture and it isparticularly difficult to accurately measure the layer thickness as afunction of the position with respect to a standard. On the other hand,the chambered member I4 disclosed herein can readily be checked on agauge, and furthermore because of the rather small size of the chamber IIS the standard glasses 52 and 56' can be kept in small'dimensions.Thus, the standards can be made more precisely and at less expense sincea larger number of standard glasses maybe cut from a piece of glasswhich has beenproved satis- "imity to a fixed standard color glass,passing light ra'ys'through said standard and through said confactory. Ii

In Figure 6 is shown diagrammatically a form of apparatus by means ofwhich a photoelectric cell can be used in the determination of theconcentration of a liquid. A base plate 80 similar to the plate 10 ofFigures 1 and 2 servesas a support for transparent member 82 containinga wedge-formed chamber 84 for the liquid to be examined. The plate 80 isadapted to rest upon a suitable support, not shown, the supportcontaining a scale 86 adapted to cooperate with an index 88 on the baseplate in a manner similar to that of scales 36 and 38 and indexes 32 and34.

A photo-electric cell 90 is arranged below the device so as to be in thepath of light rays passing from a suitable electric or other lamp 92 andthrough a lens 94 and the chamber 84. The photoelectric cell 90 isconnected to a suitable meter 96, the scale of which contains two marksdesignated a and I), each of which corresponds to a particular measuringrange as is indicated at a and b on the scale 86. It is merely necessaryto shift the base plate 80 longitudinally under the lightray to aposition where the pointer of the meter rests exactly at one of the twomarks. One may then read by the position of the chamber the hemoglobincontent of that scale a or b corresponding tothe mark on the meterindicated by the pointer.

It is to be understood that in assembling the apparatus shown in Figure6 the correct positlon of the member 82 on the plate 80 will be found inthe same manner as has been previously described with reference to theembodiment illustrated in Figure 3.

Obviously many modifications and variations I of the invention may bemade without departing from the spirit and scope thereof, and thereforeonly such limitations should be imposed as are indicated by the appendedclaims.

I claim:

1. A methodof measuring the hemoglobin content of an undiluted bloodsample comprising the steps of hemolysing the undiluted blood sample byadding thereto a small amount of saponin, placing said hemolysed bloodsample in a transparent container having an elongated chamber ofuniformly varying capillary thickness, placing said container in closeproximity to a fixed standard color glass, passing light rays throughsaid standard and through said container, moving said, containerrelatively to said color glass and in a longitudinal direction withrespect to said chamber until a color match is obtained between thecolor of the standard and the color of the sample in said chamber bytransmitted light, and determining the hemoglobin content of the bloodsample at the matching point by measuring the thickness of the chamberat said matching point.

2-. In the method of measuring the hemoglobin content of blood inaccordance with claim 1 the additional step of treating the undilutedblood sample to eliminate fluctuations in the oxygen content and theinfluence of said fluctuations on the color of the blood by mixing withsaid blood a small amount of sodium hydrosulfite.

3. A method of measuring the hemoglobin content of an undiluted bloodsample comprising the steps of simultaneously hemolysing and reducingthe sample by adding thereto asmall amount of a mixture of saponin andsodium hydrosulfite. placing said hemolysed and reduced blood sample ina transparent container having an elongated chamber of uniformly varyingcapillary thickness, placing-said container in close proxtainer', movingsaid"container relatively to said 'color glass and in-a longitudinaldirection with parent base plate having a smooth and even upper surface,a transparent member adapted to be set on the upper surface of said baseplate and having a cut-out portion in its lower side, said cut-outportion forming with the upper surface of said base plate a wedge-shapedchamber of capillary height and a transparent ledge member permanentlysecured to the upper surface of thebase plate and serving as a supportfor one side of said transparent member.

5. A device for use in the measurement of the color 01' an undilutedliquid comprising a transparent base plate having a smooth and evenupper surface, a transparent member adapted to be set on the uppersurface of said base plate and having a cut-out wedge-shaped portion inits lower side, said cut-out portion forming with the upper surface ofsaid base plate a wedge-shaped chamber of capillary height and atransparent ledge member permanently secured to the upper surface ofsaid base plate and serving as a supporting stop for. said firstmentioned transparent member, said first mentioned transparent memberand said transparent ledge member being provided with means comprising aprojection on one member and an indentation on the other member forpreventing relative longitudinal movement between said transparentmembers.

6. A device for use in the measurement of the color of an undilutedliquid comprising a transparent base plate having a smooth and evenupper surface, a transparent member adapted to be set on theuppersurface of said base plate and having a cut-out portion in itslower side, said cut-out portion forming with the upper surface of saidbase plate a wedge-shaped chamber of capillary height, a housing havingan upper supporting wall, said wall being provided with a sight opening,said base plate being adapted to be moved longitudinally on said wallwith said transparent member and said chamber over said sight opening,means for directing light'rays through said sight opening and chamberedtransparent member, means comprising a scale on said wall and acooperating index on said base plate for indicating the longitudinalposition of said base plate on said wall, a support in said housing, aglass color filter plate and a standard color glass mounted on saidsupport in super-imposed relation beneath said sight opening so thatsaid glass can be seen through said sight opening at the same time thatthe filtered light rays are seen through said chambered transparentmember.

7. A device for the measurement of the concentration of an undilutedliquid comprising a housing having a scale plate provided with a sightopening, a transparent member provided with a wedge-shaped chamberadapted to hold the liquid to be tested, said member being adapted to bemoved along said scale plate with said chamber over a portion of saidsight opening, a support in said housing, a pair of standard colorglasses of different color mounted on said support below said sightopening, means for directing light rays upwardly through said sightopening, part of said rays passing through said standard color glassesand part through the chamber con- 'taining the liquid being tested, amovable shutt-er for covering either one ofsaid standard color glasses,a pair of scales on said scale plate each 01' which scales shows ameasurement range corresponding to one of said standard color glasses, apair 01' indexes on said transparent member each of which cooperateswith one of said scales, and means on said shutter for indicating whichof said scales should be read to show the concentration of said liquid.

8. A device as described in claim 7 in which the indicating means on theshutter comprises a double-ended arrow one end of which is out of viewwhen the other end is pointing to the scale to be read.

9. A device as described in claim 7 provided with color filter glassesand means in said housing for holding said glasses in the path of thelight rays.

10. A device as described in claim 7 in which the means for directingthe light rays upwardly through the sight opening comprise an opening inthe upper portion of the housing and a mirror arranged so as to reflectupwardly through said standard color glasses and said sight openinglight rays entering said housing from an outside source through saidopening in its upper portion.

11. A method of measuring the hemoglobin content of an undiluted bloodspecimen comprising hemolysing the specimen so as to render itsubstantially transparent, reducing the specimen to eliminatefluctuation in the oxygen content thereof, placing the specimen in atransparent container having an elongated wedge-shaped chamber ofuniformly varying capillary thickness, placing said container in closeproximity to a fixed standard color glass, passing light rays throughsaid standard glass and through said container, moving said containerrelatively to said color glass in a longitudinal direction with respectto said chamber until a color match is obtained between the color of thestandard and the color of the sample in said chamber by transmittedlight, and determining the hemoglobin content of the blood sample at thematching point by measuring the thickness of the chamber at saidmatching point.

12. A method of measuring the hemoglobin con tent of an undiluted bloodsample comprising the steps of hemolysing the undiluted blood sample,placing said sample in a transparent container having an elongatedchamber of uniformly varying capillary thickness, placing said containerin close proximity to a fixed standard color glass, passing light raysthrough said standard glass and through said container, moving saidcontainer relatively to said color glass and in a longitudinal directionwith respect to said chamber until a color match is obtained between thecolor of the standard and the color of the sample in said chamber bytransmitted light, and determining the hemoglobin content of the bloodsample at the matching point by measuring the thickness of the chamberat said matching point.

13. A device as described in claim 4 in which the transparent memberisshorter than the base plate and longer than said ledge member so thatsaid transparent member may rest on portions of said base plate whichare distant from the ends 01' the ledge member so as to be substantiallyfree from dirt which may collect around the ends of said ledge member.

MICHAEL PHILIPSEN.

